In article ,
Dave Plowman (News) wrote:

The normal kitchen drain plumbing should cope with two washing machine
wastes given that it will cope with a washing machine, dishwasher and sink
all draining at once. Although this should be uncommon anyway.

Funny you should say this...

I discovered yesterday that when our washing machine pumps out at the same
time as the dishwasher *and* I have a tap running it overflows the standpipe
from the washing machine :-(

Current setup is 2 washing machine traps - one for each of the appliances
(http://www.screwfix.com/app/sfd/cat/...37821&id=18640 ) and then
a normal trap under the sink. The drain then runs through the wall and into
the concrete slab under the conservatory :-(

Its a bit sludged up but nothing major - certainly nothing suggesting
that it is seriously bunged up anywhere so I can only assume that our
new(ish) Miele washing machine and dishwasher has a much more powerful
pump than the knackered hoover models that they replaced...

Suggestions? Would a couple of self cutting washing machine thingys
(http://www.screwfix.com/app/sfd/cat/...37176&id=11879 ) help
by restricting the output from the machine maybe? Or are they not
restrictive at all (never actually seen one to examine...)

I guess it must be time for us to have another Caustic Soda thread so
maybe I'll try some of that


Darren